Removal of Trypanosoma cruzi by white cell-reduction filters: an electronmicroscopic study

White cell (WBC)-reduction filters have been shown to be effective in removing infectious agents from infected blood products. In this study, the mechanisms of Trypanosoma cruzi (T. cruzi) retention by WBC-reduction filters were assessed. Human packed red blood cell (PRBC) and platelet concentrate (PC) samples were contaminated with T. cruzi organisms (Y strain; 3.4 x 10(6)/ml), and then filtered using WBC-reduction experimental filters that provided about 3 log10 WBC removal. Transmission electron microscopy sections showed that T. cruzi parasites were removed from contaminated PRBC and PC samples primarily by mechanical mechanism without interacting with filter fibbers or blood cells. In addition, we found that T. cruzi parasites were also removed by a direct fibber adhesion. These data indicate that T. cruzi parasites are removed from infected blood not only by mechanical mechanism but also by biological mechanism probably mediated by parasite surface proteins.

Winning the war for talent: Does CSR matter in the recruitment process?

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

A matter of time: Phases of customer co-creation community participation and their impact on customer behavior

Despite the growing relevance of co-creating customer communities only little scientific evidence is available on their impact on transactional behavior of participants. Previous research has mostly used self-reported data or distinguished only between during and pre-community phases obtaining mixed results. However, the author proposes that co-creating community activity takes place in five distinguishable phases and changes in transactional behavior are limited to certain phases. Using 33 months of transactional data of a Dutch online auction provider a study was conducted covering all five phases of the community co-creation process from community planning over community set-up, co-development and co-testing to post-launch. The overall results indicate mixed effects of community participation on the different transactional variables during the co-creation process. Community participation had positive effects on auctions listing behavior at the community set-up, co-development and post-launch phases, whereby the number of auctions listed peaked during the community set-up phase. These results suggest that the impact on transactional behavior differs between co-creation phases and different psychological mechanism limited to certain phases might trigger the respective changes.

White piedra: molecular identification of Trichosporon inkin in members of the same family

INTRODUCTION: White piedra is a superficial mycosis caused by the genus Trichosporon and characterized by nodules on hair shaft. METHODS: The authors report a family referred to as pediculosis. Mycological culture on Mycosel® plus molecular identification was performed to precisely identify the etiology. RESULTS: A Trichosporon spp. infection was revealed. The molecular procedure identified the agent as Trichosporon inkin. CONCLUSIONS: White piedra and infection caused by T. inkin are rarely reported in Southern Brazil. The molecular tools are essentials on identifying the Trichosporon species.

Do social factors matter for innovation, and do they influence innovation in Aeronautics Industry?

Based on the report for the course on “Social Factors of Innovation” of the PhD Program on Technology Assessment, supervised by Prof. António Brandão Moniz, Monte de Caparica, University NOVA Lisbon, Faculty of Sciences and Technology, July 2013

Does ownership structure matter? Three essays in finance

Management

Control of a white organic light emitting diode’s emission parameters using a single doped RGB active layer

White Color tuning is an attractive feature that Organic Light Emitting Diodes (OLEDs) offer. Up until now, there hasn’t been any report that mix both color tuning abilities with device stability. In this work, White OLEDs (W-OLEDs) based on a single RGB blend composed of a blue emitting N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) doped with a green emitting Coumarin-153 and a red emitting 4-(Dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM1) dyes were produced. The final device structure was ITO/Blend/Bathocuproine (BCP)/ Tris(8-hydroxyquinolinato)aluminium (Alq3)/Al with an emission area of 0.25 cm2. The effects of the changing in DCM1’s concentration (from 0.5% to 1% wt.) allowed a tuning in the final white color resulting in devices capable of emitting a wide range of tunes – from cool to warm – while also keeping a low device complexity and a high stabilitty. Moreover, an explanation on the optoelectrical behavior of the device is presented. The best electroluminescense (EL) points toward 160 cd/m2 of brightness and 1.1 cd/A of efficiency, both prompted to being enhanced. An Impedance Spectroscopy (IS) analysis allowed to study both the effects of BCP as a Hole Blocking Layer and as an aging probe of the device. Finally, as a proof of concept, the emission was increased 9 and 64 times proving this structure can be effectively applied for general lighting.

Dry matter allocation in Jessenia bataua (PALMAE)

There are few assessments of lifetime dry matter production for tropical trees. However, several studies, have been carried out for palms. This study measures dry matter production for Jessenia bataua,a useful palm common in many areas of the Amazon Valley. Palms In the Ducke Forest Reserve Of INPA were studied. Approximately 34% of total aboveground dry matter production in this palm was, alllocated to reproductive effort, eg., the production of in florescences and fruits. The meaning of this percentage, to discussed, relative to percentages identified in other Neotropical palms.

Audit quality: does gender composition of audit firms matter?

Using a sample of Portuguese audit firms and their client companies, this study examines the association between gender composition of the partnership structure oaudit firms and audit quality. Audit quality is measured through the earnings quality of audit clients. We find that gender diversity in the partnership structure of audit firms, per se, has no association with audit quality. In turn, we find significant evidence that a predominant presence of female Certified Public Accountants (CPAs) in partner positions in audit firms is associated with higher audit quality. In particular, the results indicate that audit firms with female-dominated partnership structures are negatively related with aggressive accounting practices in audit clients.

A synopsis of the species of Mesovelia (Insecta: Heteroptera: Mesoveliidae) occurring in the floodplain of the Amazon River, Brazil, with redescriptions of Mesovelia mulsanti White and M. zeteki Harris & Drake

Mesovelia mulsanti White, 1879 and M. zeteki Harris & Drake, 1941 are newly recorded in the Amazon River floodplain, Brazil. A key to the three known species ocurring in this region is also provided. Mesovelia mulsanti can be distinguished from M. amoena and M. zeteki by the body length larger than 2.50 mm, the head without longitudinal brown stripes near midline, and the forefemur and midfemur of the male, which have ventral rows of spines. Mesovelia amoena differs from M. zeteki in aspects of body color and in number of spinules near posterior margin of abdominal sternite VI of male.

Search for dark matter in events with heavy quarks and missing transverse momentum in pp collisions with the ATLAS detector

This article reports on a search for dark matter pair production in association with bottom or top quarks in 20.3fb−1 of pp collisions collected at s√=8 TeV by the ATLAS detector at the LHC. Events with large missing transverse momentum are selected when produced in association with high-momentum jets of which one or more are identified as jets containing b-quarks. Final states with top quarks are selected by requiring a high jet multiplicity and in some cases a single lepton. The data are found to be consistent with the Standard Model expectations and limits are set on the mass scale of effective field theories that describe scalar and tensor interactions between dark matter and Standard Model particles. Limits on the dark-matter--nucleon cross-section for spin-independent and spin-dependent interactions are also provided. These limits are particularly strong for low-mass dark matter. Using a simplified model, constraints are set on the mass of dark matter and of a coloured mediator suitable to explain a possible signal of annihilating dark matter.

On the Hill estimator: a comparison of methods

Extreme value theory (EVT) deals with the occurrence of extreme phenomena. The tail index is a very important parameter appearing in the estimation of the probability of rare events. Under a semiparametric framework, inference requires the choice of a number k of upper order statistics to be considered. This is the crux of the matter and there is no definite formula to do it, since a small k leads to high variance and large values of k tend to increase the bias. Several methodologies have emerged in literature, specially concerning the most popular Hill estimator (Hill, 1975). In this work we compare through simulation well-known procedures presented in Drees and Kaufmann (1998), Matthys and Beirlant (2000), Beirlant et al. (2002) and de Sousa and Michailidis (2004), with a heuristic scheme considered in Frahm et al. (2005) within the estimation of a different tail measure but with a similar context. We will see that the new method may be an interesting alternative.

Does dosage in abstinence education matter?

Although past reviews uniformly criticized the efficacy and effectiveness of sexual abstinence in adolescents, new studies dispute the earlier findings. Studies that unpackage intervention programs provide one means of understanding why they succeed in some settings and not in others. This study examined 3183 students spread over 35 schools on the number of hours that they received in sexual abstinence education, in a context of health behaviors promotion. A multi-level analysis (HLM) was performed. The number of hours did not appear to make any difference in the outcome scores. Reasons for this finding are presented and their implications are provided.

Tree communities of white-sand and terra-firme forests of the upper Rio Negro

The high tree diversity and vast extent of Amazonian forests challenge our understanding of how tree species abundance and composition varies across this region. Information about these parameters, usually obtained from tree inventories plots, is essential for revealing patterns of tree diversity. Numerous tree inventories plots have been established in Amazonia, yet, tree species composition and diversity of white-sand and terra-firme forests of the upper Rio Negro still remain poorly understood. Here, we present data from eight new one-hectare tree inventories plots established in the upper Rio Negro; four of which were located in white-sand forests and four in terra-firme forests. Overall, we registered 4703 trees > 10 cm of diameter at breast height. These trees belong to 49 families, 215 genera, and 603 species. We found that tree communities of terra-firme and white-sand forests in the upper Rio Negro significantly differ from each other in their species composition. Tree communities of white-sand forests show a higher floristic similarity and lower diversity than those of terra-firme forests. We argue that mechanisms driving differences between tree communities of white-sand and terra-firme forests are related to habitat size, which ultimately influences large-scale and long-term evolutionary processes.